San Pedro River Flow Disappearing Near Fort Huachuca for Third TimeLocal Efforts to Control Excessive Groundwater Pumping Failing as
Base Cleared for Massive New Expansion

SIERRA VISTA, Ariz.— San Pedro River stream flow is disappearing east of Fort Huachuca at the Charleston gage for the third straight year and for the third time since measurements began in 1904. Charleston gage stream flow is the most sensitive indicator of the health of the San Pedro River and the Upper San Pedro watershed’s groundwater aquifer.

The San Pedro River is the last surviving wild desert river in the Southwest; its cottonwood/willow forest is the best surviving example of the rarest forest type in North America. During the driest time of the year, critical stream flow comes directly from underground aquifer water seeping through from the river’s banks.

Zero stream flow near Fort Huachuca results from the combination of three significant factors: (1) drought, including diminished winter monsoon rain; (2) water absorption by streamside vegetation; and (3) excessive local groundwater pumping. “We cannot control drought or lack of winter monsoon rain, but we can control excessive groundwater pumping,” says Dr. Robin Silver, Center for Biological Diversity board chair.

Fort Huachuca is the Sierra Vista area’s major economic driver; two-thirds of the businesses in Sierra Vista are military driven. In 2002, groundwater pumped from the aquifer exceeded replenishment by 5,144 acre-feet per year. At the time, Fort Huachuca acknowledged responsibility for 54 percent of the deficit, or 2,784 acre-feet per year. Since 2002, Fort Huachuca has increased its local expenditures in Cochise County by 81 percent, from $528 million to $955 million. Groundwater pumping now exceeds replenishment by 11,300 acre-feet per year.

In spite of increasing San Pedro peril, Fort Huachuca’s mitigation requirement has been reduced by the U.S. Fish and Wildlife Service to facilitate massive new base expansion. Fort Huachuca now only owns responsibility for 31 percent of the deficit, or 3,530 acre-feet per year. Clearance for Fort Huachuca’s massive expansion and reduced mandatory mitigation despite obvious increasing risk to the river are based on two factors: (1) a new creative “per capita” water mitigation accounting scheme designed to underestimate the Fort’s groundwater pumping responsibility, and (2) a 2003 Rick Renzi congressional legislative rider precluding consideration of the San Pedro’s declining condition in any evaluation of Fort Huachuca’s environmental effects.

“The Renzi rider is the equivalent of allowing a surgeon to perform unnecessary cosmetic surgery on a frail, elderly patient. The outcome is predictably fatal,” says Silver. “And the new water-mitigation accounting scheme benefiting developers to the detriment of the San Pedro? From the Bush administration,
this is not surprising.”